Fuel Odor in Cab

[RonMele]

Yeah, I'm the same guy with the sparky heater switch...so you can imagine my concerns over a fairly strong raw fuel odor I've had in the 66 cab since I finished the restoration a couple years ago and started driving the truck. I've checked all the standard stuff to no avail and really would like to resolve this before I start driving the truck again this season. What have I checked? Well, I have the correct hose from the tank to the filler cap...nice and tight. I've replaced the fuel line from the tank all the way to the rubber hose under the cab...replaced that hose as well. (Now come to think of it...did I replace the line from that hose to the fuel pump? Hmm. Have a good gasket at the fuel sending unit. Am I missing something? (Note to self...check that other line!)
Thanks,
Ron

[skidoorulz]

Really really small pin hole in tank due to rust? Or a really really small seep at the seam on the tank due to rust?

[64 f100]

One mistake is overfilling the tank. When the gas expands from heat in the summer it sometimes will push out the gas cap and run down to the rubber seal on the fill pipe and into the cab. Also does the same thing if overfull and you park on a hill with the drivers side lower than the passenger side.

Rich

[RonMele]

Thanks. I am certain I am not over-filling the tank...only put in a few gallons at at time. Going to the Secret Location (garage where I hide this truck) in April to take her out...I think maybe a soapy water check with a little air pressure in the tank might identify a pinhole leak...good thought. These tanks are available and I have some holly green paint...so I suspect a fuel tank swapout this Spring might be in order

[bruceandersson]

JUst because you smell it in the cab, does not mean that where the problem is. Does the smell occur at all times or after driving or after filling? Have you looked at everything from tank to carb when the smell is present?

[62bigwindow]

I just had this problem with my '56 Ranch Wagon. I determined that the fuel sending unit gasket was bad allowing fumes to escape into the passenger compartment. I replaced it and have not had another problem.

[ICEMAN6166]

just got over that issue with my rambler

fuel pump was spitting out the weep hole
fuel pump for that was obsoleted so now i have an electric pump but the smell is gone.

[62bigwindow]

One other thing to look at is the filler cap.I am not sure about your truck but some require a vented cap.

[RonMele]

Hey Gang,

Thought I would update the status of this problem. When I originally posted this issue I got a number of suggestions on where the source was. It took me a while to get back to the truck and yesterday we were going to do a soapy water leak check along the top seam, sending unit cover, filler hose, etc. While inspecting the other seams I noticed that one of the anti-mouse Bounce sheets I had in the cab near the tank was stained. Sure enough...smelled like gas. It turns out that I had a seep coming from the bottom of the tank near where the tank meets the combo tank bracket/cab mount. When I was disassembling this truck for it's cancer treatment I recalled both cab mounts being completed corroded and unusable; it never occurred to me that these open holes could very likely have led to the tank getting corroded and causing a leak. We never detected a fuel leak in the cab because back then we were tuning/repairing/running the engine from an old lawnmower fuel tank in the engine compartment. So my lesson learned on this one was to either leak check the tank BEFORE reusing it...or just pony up and get a new one (like I did for the current project...a 1950 Ford Deluxe Custom Coupe).